As demands for more digital information and bigger data size grow considerably, the related industries have been trying to develop better transmission quality and better real-time computing. These demands promote the development of the high-speed signal transmission technology. In addition to changing signal codes, reducing signal level and providing full-duplex transmission mode can also increase signal transmission speed and reduce users' time for waiting. In this method, stringent standards regarding signal attenuation and distortion as well as noise interference are applied. Hence, quality and speed of the signal transmission of the connector is crucial. USB 2.0 connectors have been introduced in the year of 2000 and its maximum transmission speed is 480 Mbps. In 2008, a full-duplex USB 3.0 connectors have been introduced and its maximum transmission speed is 4.8 Gbps which is ten times the speed of the USB 2.0 connectors. Apart from the advantage of the transmission speed, USB 3.0 connectors are capable of backward compatibility so that USB 3.0 connectors are widely used in the electronic devices.
However, high-speed signal transmission comes with the high-frequency and high-energy electromagnetic signals. These electromagnetic signals result in delay, disconnection and bad transmission quality of the wireless devices around the electronic device (e.g., wireless keyboards, mouses, 802.11b/g/n and Bluetooth). Therefore, it is crucial to suppress electromagnetic interference (EMI) and electromagnetic compatibility (EMC).